And your box is now ready to be put on the wall where the collision has to be. From now on, only move the box to move the magnet.

Now make a wall, I did this with a second box scaled up to X and Y 1000.
Place the wall wherever you want, I put it slightly behind the blue magnet box.

It should look something like this.

Poser 1, 2, 3, 4, 5, 7, P8 and PPro2010, P9 and PP2012, P10 and PP2014 Game Dev
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